Oil passage control device for transfer case

Abstract

The utility model discloses a kind of oil circuit control devices for transfer case, including flow distribution control box, three vertical flow guide grooves are formed on the front wall surface of flow distribution control box, three vertical flow guide grooves are communicated with the corresponding three oil inlet holes of transfer case respectively and correspond;The bottom surface of flow distribution control box is formed with three left and right arrangement upward extending step holes, the bottom surface of flow distribution control box is fixed with three plug-in valves, the stem of plug-in valve is inserted in the corresponding step hole, the step hole includes the first hole section, the second hole section, the third hole section and the fourth hole section that inside diameter gradually decreases from bottom to top, the outside wall of the stem of plug-in valve is formed with corresponding annular extension part;It reduces the impact force of oil liquid entering wet clutch push piston block by the buffering effect of valve core, buffering small spring and buffering big spring, so that corresponding piston block is slowly pushed, realizes the stability when shifting, improves driving comfort.

Description

Technical Field

[0001] This utility model relates to the field of power transmission technology, and more specifically to an oil circuit control device for a transfer case. Background Technology

[0002] Currently, the drive mechanism of four-wheel drive forklifts is equipped with a transfer case, which is used for switching between two-wheel drive and four-wheel drive. It usually has multiple gears to achieve gear shifting.

[0003] When a wet clutch is installed in the transfer case, hydraulic oil is required to control the opening and closing of the wet clutch. For a conventional diesel off-road forklift, the engine drives the oil supply pump to provide the corresponding hydraulic oil to the wet clutch so as to realize the normal opening and closing of the wet clutch. The oil supply pump is installed on the transfer case.

[0004] In some existing off-road forklifts, sufficient torque is required. These forklifts use an engine-driven hydraulic pump, which in turn drives a hydraulic motor, which in turn powers the transfer case. Since these transfer cases lack an oil supply pump, they cannot operate the wet clutch mechanism found in gearboxes. Therefore, an independent hydraulic circuit control device is needed. This device supplies oil to the hydraulic circuit control unit via a corresponding hydraulic pump, which then controls the oil flow into the wet clutch within the transfer case, pushing the piston to engage and disengage the clutch. However, existing hydraulic circuit control devices lack a buffer structure, resulting in excessive impact force during oil intake. This excessive impact causes the wet clutch piston to engage rapidly, leading to significant jerking during gear shifts and impacting driving comfort. Utility Model Content

[0005] The purpose of this utility model is to overcome the shortcomings of the prior art and provide a hydraulic control device for a transfer case. It reduces the impact force of the oil entering the wet clutch to push the piston block through the buffering effect of the valve core, the small buffer spring and the large buffer spring, so that the corresponding piston block is pushed slowly, thereby achieving stability during gear shifting and improving driving comfort.

[0006] The solution of this utility model to the aforementioned technical problem is:

[0007] A transfer case oil circuit control device includes a flow distribution control box, wherein three vertical flow guide grooves are formed on the front wall surface of the flow distribution control box, and the three vertical flow guide grooves are respectively connected to and correspond to the three corresponding oil inlets of the transfer case;

[0008] The bottom surface of the flow control box is formed with three stepped holes arranged horizontally and extending upwards. Three cartridge valves are fixed on the bottom surface of the flow control box. The stem of the cartridge valve is inserted into the corresponding stepped hole. The stepped hole includes a first hole section, a second hole section, a third hole section, and a fourth hole section whose inner diameter gradually decreases from bottom to top. A corresponding annular extension is formed on the outer wall of the stem of the cartridge valve. The annular extension is inserted into the lower part of the corresponding first hole section, second hole section, or third hole section. The outer wall of the sealing layer on its outer wall is pressed against the inner wall of the corresponding hole section.

[0009] The top surface of the fourth hole section has an upwardly extending upper connecting hole formed in the middle, and the upper connecting hole communicates with the corresponding valve core mounting hole formed on the top surface of the flow control box.

[0010] An oil buffer device is installed in the valve core mounting hole.

[0011] The oil buffer device includes a valve core, a large buffer spring, and a small buffer spring. The valve core, the large buffer spring, and the small buffer spring are inserted into the corresponding valve core mounting holes. A sealing nut is screwed to the top of the valve core mounting hole. The small buffer spring is inserted into the large buffer spring. The tops of the large buffer spring and the small buffer spring press against the bottom end face of the sealing nut. The bottom ends of the large buffer spring and the small buffer spring exert force on the top surface of the valve core. The rod part formed in the middle of the top surface of the valve core is inserted into the lower part of the small buffer spring. The outer side wall of the valve core is close to the inner side wall of the valve core mounting hole. Multiple annular liquid guide grooves are formed on the outer side wall of the valve core.

[0012] The upper part of the left side wall of the flow control box is formed with a main return hole extending to the right, which passes through three valve core mounting holes. A plug is fixed at the left end of the main return hole. The bottom surface of the left side of the flow control box is formed with an upward-extending vertical return hole, the upper part of which communicates with the main return hole. A lower plug is fixed at the bottom end of the vertical return hole. The rear part of the lower part of the left side wall of the flow control box is formed with a main oil inlet hole extending to the right, which passes through the upper part of the second section of the three stepped holes and communicates with the second section of the three stepped holes. A plug is fixed at the right end of the main oil inlet hole.

[0013] The lower rear part of the left side wall of the distribution control box is formed with a lower oil return hole extending to the right. The lower oil return hole penetrates the upper part of the first hole section of the three stepped holes and communicates with the vertical return hole. A plug is fixed to the right end of the lower oil return hole.

[0014] The rear wall of the flow control box has three through holes extending backward. The middle part of the through hole is connected to the corresponding upper connecting hole, the rear end of the through hole is connected to the corresponding vertical flow guide groove behind it, and the front end of the through hole is fixed with a plug.

[0015] The outstanding effect of this utility model is:

[0016] Compared with existing technologies, it reduces the impact force of the oil entering the wet clutch to push the piston block through the buffering effect of the valve core, the small buffer spring and the large buffer spring, so that the corresponding piston block is pushed slowly, thereby achieving stability during gear shifting and improving driving comfort. Attached Figure Description

[0017] Figure 1 This is a partial structural diagram of the present invention installed in the transfer case;

[0018] Figure 2 This is a partial structural diagram of the flow control box as a whole;

[0019] Figure 3 This is a partial cross-sectional view of the through hole at the right end of the overall flow control box;

[0020] Figure 4 This is a partial perspective view of the flow control box as a whole;

[0021] Figure 5 This is a partial sectional view of the flow control box;

[0022] Figure 6 yes Figure 5 A schematic diagram of the local structure from a different angle;

[0023] Figure 7 This is a partial cross-sectional view of the through hole at the left end of the overall flow control box;

[0024] Figure 8 It is a partial cross-sectional view of the front section connected at the through hole in the middle of the overall flow control box;

[0025] Figure 9 This is a partial cross-sectional view showing the rear section connected at the through-hole in the middle of the overall distribution control box. Detailed Implementation

[0026] For example, see below. Figures 1 to 9 As shown, a transfer case oil circuit control device includes a flow control box 10, which is fixed on the outer wall of the transfer case mounting location. A sealing gasket is sandwiched between the front wall of the flow control box 10 and the outer wall of the transfer case mounting location. Three vertical flow guide grooves 11 are formed on the front wall of the flow control box 10, and the three vertical flow guide grooves 11 are respectively connected to and correspond to the three corresponding oil inlets of the transfer case.

[0027] The bottom surface of the flow control box 10 is formed with three stepped holes 12 arranged horizontally and extending upwards. Three cartridge valves 13 are fixed to the bottom surface of the flow control box 10 (since the cartridge valves 13 are existing known components, and are also commercially available in this embodiment, their internal structure is omitted from the attached drawings; the drawings are for illustrative purposes only). The stems of the cartridge valves 13 are inserted into the corresponding stepped holes 12. The stepped holes 12 include a first section, a second section, a third section, and a fourth section whose inner diameter gradually decreases from bottom to top. The outer side wall of the rod body is formed with a corresponding annular extension, which is inserted into the lower part of the corresponding first hole section, second hole section or third hole section. The outer side wall of the sealing layer on its outer side wall is pressed against the inner side wall of the corresponding hole section. The side wall of the rod body facing the upper part of the first hole section is formed with a side return oil through hole, and the side wall of the rod body facing the upper part of the second hole section is formed with a side inlet oil through hole. The top surface of the rod body is formed with a downward extending cavity. The valve core rod of the cartridge valve 13 is inserted into the cavity, and its top end is inserted into the top of the rod body and covers the top end of the cavity.

[0028] The top surface of the fourth section has an upwardly extending upper connecting hole formed in the middle. The upper connecting hole communicates with the corresponding valve core mounting hole 14 formed on the top surface of the flow control box 10. The inner diameter of the valve core mounting hole 14 is larger than the inner diameter of the upper connecting hole. The valve core 15, the buffer large spring 16, and the buffer small spring 17 are inserted into the corresponding valve core mounting hole 14. A sealing nut is screwed to the top of the valve core mounting hole 14. The buffer small spring 17 is inserted into the buffer large spring 16. The tops of the buffer large spring 16 and the buffer small spring 17 press against the bottom end face of the sealing nut. The bottom ends of the buffer large spring 16 and the buffer small spring 17 exert force on the top surface of the valve core 15. The rod part formed in the middle of the top surface of the valve core 15 is inserted into the lower part of the buffer small spring 17. The outer side wall of the valve core 15 is close to the inner side wall of the valve core mounting hole 14 (with a gap of 0.02mm to 0.05mm). Multiple annular liquid guide grooves are formed on the outer side wall of the valve core 15.

[0029] The upper part of the left side wall of the flow control box 10 is formed with a main return hole 18 extending to the right. The main return hole 18 passes through three valve core mounting holes 14, so that the three valve core mounting holes 14 communicate with the main return hole 18. A sealing head is fixed at the left end of the main return hole 18. The bottom surface of the left side of the flow control box 10 is formed with an upwardly extending vertical return hole 19. The upper part of the vertical return hole 19 communicates with the main return hole 18. A lower sealing head is fixed at the bottom end of the vertical return hole 19. The lower part of the left side wall of the flow control box 10 is rear The main oil inlet 101 extends to the right and penetrates the upper part of the second section of the three stepped holes 12 and communicates with the second section of the three stepped holes 12. A plug is fixed to the right end of the main oil inlet 101. The lower rear part of the left side wall of the distribution control box 10 has a lower oil return hole 102 extending to the right and penetrates the upper part of the first section of the three stepped holes 12. The lower oil return hole 102 communicates with the vertical return hole 19. A plug is fixed to the right end of the lower oil return hole 102.

[0030] Three through holes 103 extending rearward are formed on the rear wall of the flow control box 10. The middle part of the through hole 103 is connected to the corresponding upper connecting hole. The rear end of the through hole 103 is connected to the corresponding vertical flow guide groove 11 behind. A plug head is fixed to the front end of the through hole 103. In this embodiment, in order to ensure that the rear end of the through hole 103 communicates with the corresponding vertical flow guide groove 11, part of the through hole 103 is a straight through hole, and part is a bent through hole or other shaped through hole. It is only necessary to ensure that the rear end of the through hole 103 communicates with the corresponding vertical flow guide groove 11. For example, in the middle through hole 103, the front through hole 103 communicates with the middle upper connecting hole, one end of the rear through hole 103 communicates with the fourth hole segment of the middle stepped hole 12, and the other end communicates with the corresponding vertical flow guide groove 11. The through hole 103 on the left side is a series of bends that communicate with the corresponding vertical flow guide groove 11.

[0031] In use, after removing the plug of the main oil inlet 101, connect it to the oil inlet pipe. After removing the plug of the main oil return 88, connect it to the oil return pipe. The oil inlet pipe is connected to the outlet of the main control valve connected to the hydraulic pump. The oil return pipe is connected to the inlet of the oil return valve. The outlet of the oil return valve is connected to the hydraulic oil tank. The inlet of the hydraulic pump is connected to the hydraulic oil tank. The hydraulic pump, the main control valve and the cartridge valve 13 are all electrically connected to the control host through electrical connection lines. The operation is controlled by the control host. Its structure is the existing conventional structure, which will not be described in detail here. Some structures are also omitted in the attached drawings.

[0032] When in use and in neutral, the oil from the main oil inlet 101 enters all the second sections, and then enters the cavity of the rod of the cartridge valve 13 through the side oil inlet throughlet and flows out through the side return oil hole into the first section, and then into the lower return oil hole 102. After that, it enters the main return oil hole 18 through the vertical return oil hole 19 and then flows out through the return oil pipe.

[0033] When the corresponding gear is engaged, the valve core rod of the corresponding cartridge valve 13 retracts, and the outer wall of the end of the rod covers all the corresponding side return oil holes. At this time, the oil enters from the side oil inlet hole, flows upward to the third hole section, enters the upper connecting hole, enters the corresponding vertical guide groove 11, and then enters the corresponding oil inlet hole or the second oil inlet hole. This causes the corresponding first gear clutch piston 48, second gear clutch piston 49, or third gear clutch piston 51 to be pushed, so that the corresponding driven friction plate 2 and driving friction plate 1 are pressed together, thereby realizing the transmission of power. In addition, some oil will enter from the side oil inlet holes of the other two cartridge valves 13 and then flow back from the side return oil hole, just like in neutral.

[0034] When the oil is injected, the pressure is too high at once, and the upward surge of the oil pushes the corresponding valve core 15 upward. The valve core 15 is supported by the corresponding small buffer spring 17 and large buffer spring 16, thus buffering the oil. This prevents the oil entering the vertical guide groove 11 from having an excessive impact, ensuring that when it enters the wet clutch of the transfer case and pushes the corresponding piston block, the action is slow and stable. This allows the driven friction plate and the driving friction plate of the wet clutch to be pressed together slowly, rather than being pressed together all at once, thereby improving the comfort of use and reducing the jerking sensation when shifting gears.

[0035] When the oil impacts the valve core 15, some of the oil will flow from the gap between the valve core 15 and the inner wall of the valve core mounting hole 14 into the valve core mounting hole 14, and then flow out through the main return hole 18.

[0036] When the driven and driving friction plates of the wet clutch do not need to be pressed together, i.e. when they are separated, the valve core rod of the corresponding cartridge valve 13 can simply be pushed back to its original position, which is very convenient.

[0037] In this embodiment, sealing components such as sealing rings are installed in many locations. Since they are conventional structures, they will not be described in detail here. Similarly, the connection methods and settings of some sealing heads are also existing conventional settings, and will not be described in detail here.

[0038] Finally, the above embodiments are only used to illustrate the present utility model and are not intended to limit the present utility model. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present utility model. Therefore, all equivalent technical solutions also fall within the scope of the present utility model, and the patent protection scope of the present utility model should be defined by the claims.

Claims

1. A hydraulic control device for a transfer case, comprising a flow control box (10), characterized in that: The front wall of the flow control box (10) is formed with three vertical flow guide grooves (11), which are respectively connected to and correspond to the three oil inlets of the transfer case; The bottom surface of the flow control box (10) is formed with three stepped holes (12) arranged horizontally and extending upward. Three cartridge valves (13) are fixed on the bottom surface of the flow control box (10). The stem of the cartridge valve (13) is inserted into the corresponding stepped hole (12). The stepped hole (12) includes a first hole section, a second hole section, a third hole section and a fourth hole section whose inner diameter gradually decreases from bottom to top. The outer side wall of the stem of the cartridge valve (13) is formed with a corresponding annular extension. The annular extension is inserted into the lower part of the corresponding first hole section, second hole section or third hole section. The outer side wall of the sealing layer on its outer side wall is pressed against the inner side wall of the corresponding hole section. The top surface of the fourth hole section has an upwardly extending upper connecting hole formed in the middle, and the upper connecting hole communicates with the corresponding valve core mounting hole (14) formed on the top surface of the flow control box (10). An oil buffer device is installed in the valve core mounting hole (14).

2. The hydraulic control device for a transfer case according to claim 1, characterized in that: The inner diameter of the valve core mounting hole (14) is larger than the inner diameter of the upper connecting hole.

3. The hydraulic control device for a transfer case according to claim 1, characterized in that: The oil buffer device includes a valve core (15), a large buffer spring (16), and a small buffer spring (17). The valve core (15), the large buffer spring (16), and the small buffer spring (17) are inserted into the corresponding valve core mounting holes (14). A sealing nut is screwed to the top of the valve core mounting hole (14). The small buffer spring (17) is inserted into the large buffer spring (16). The tops of the large buffer spring (16) and the small buffer spring (17) press against the bottom surface of the sealing nut. The bottoms of the large buffer spring (16) and the small buffer spring (17) exert force on the top surface of the valve core (15). The rod part formed in the middle of the top surface of the valve core (15) is inserted into the lower part of the small buffer spring (17). The outer side wall of the valve core (15) is close to the inner side wall of the valve core mounting hole (14). Multiple annular liquid guide grooves are formed on the outer side wall of the valve core (15).

4. The hydraulic control device for a transfer case according to claim 1, characterized in that: The upper part of the left side wall of the flow control box (10) is formed with a main return hole (18) extending to the right. The main return hole (18) passes through three valve core mounting holes (14), so that the three valve core mounting holes (14) are connected to the main return hole (18). A plug is fixed at the left end of the main return hole (18). The bottom surface of the left side of the flow control box (10) is formed with an upwardly extending vertical return hole (19). The upper part of the vertical return hole (19) is connected to the main return hole (18). A lower plug is fixed at the bottom end of the vertical return hole (19). The rear part of the lower part of the left side wall of the flow control box (10) is formed with a main oil inlet hole (101) extending to the right. The main oil inlet hole (101) passes through the upper part of the second hole section of the three stepped holes (12) and is connected to the second hole section of the three stepped holes (12). A plug is fixed at the right end of the main oil inlet hole (101).

5. The hydraulic control device for a transfer case according to claim 4, characterized in that: The lower rear part of the left side wall of the distribution control box (10) is formed with a lower oil return hole (102) extending to the right. The lower oil return hole (102) penetrates the upper part of the first hole section of the three stepped holes (12). The lower oil return hole (102) is connected to the vertical return hole (19). A plug is fixed at the right end of the lower oil return hole (102).

6. The hydraulic control device for a transfer case according to claim 1, characterized in that: The rear wall of the flow control box (10) has three through holes (103) extending backward. The middle part of the through hole (103) is connected to the corresponding upper connecting hole. The rear end of the through hole (103) is connected to the corresponding vertical flow guide groove (11) behind. A plug is fixed at the front end of the through hole (103).

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